JSON Viewer — Free, Open-Source, Zero Limits, One File
I built a JSON visualizer that does one thing and does it well: turn raw JSON into a clean, collapsible, color-coded tree view. No sign-ups, no file size limits, no server uploads — everything runs 100% client-side in a single HTML file.
The tool supports drag & drop, paste, and file upload. It validates JSON on the fly, highlights syntax errors, and lets you expand/collapse nested objects with a click. Perfect for developers who just want to quickly inspect an API response or debug a config file without pasting sensitive data into some random website. Completely free and open source.